Rotary drum for fissuring acoustical material



Aug. 19, 1969 c. w. .GRIFFEN 3 ,461,754 ROTARY DRUM FOR FISSURING ACOUSTICAL MATERIAL Filed Dec. 7. 1966 2 Sheets-Sheet 1 CHARLES W GRIFFEN ATTORNEY INVENTOR Aug. 19, 1969 c. w. GRIFFEN 3,461,754

I ROTARY DRUM Fox nssunme ACOUSTICAL MATERIAL Filed Dec. 9, 1966 v 2 Sheets-Sheet 2 CHARLES W- GRFFEN ATTORNEY United States Patent U.S. Cl. 83-2 6 Claims ABSTRACT OF THE DISCLOSURE A rotary drum for fissuring acoustical material having the drum surface composed of a plurality of polygonal shaped blocks. The blocks are individually formed with the projections for fissuring the acoustical material and the blocks are fastened in a removable manner to the drum surface.

Background of the invention The invention is related to the field of art concerning the use of impression-forming tools for producing fissures in acoustical material to produce an acoustical fissured ceiling material.

The prior are devices for producing fissures were either fiat plate or arcuate plates attached to a cylinder as disclosed in Patent 3,202,025. The plates were generally large to prevent a pronounced repeat design and were formed by either casting or inserting therein the pins and nails for forming the fissures. When in use, the various projections for forming the fissures would tend to wear or be broken off. Consequently, over a prolonged period of time the large cast plates would need replacement or the individual broken pieces would need to be drilled out and replacements inserted therefor. Such operations would be both costly and time consuming. Furthermore, rather noticeable and lengthy straight-line stretches of unfissured areas would appear on the acoustical material in those regions where the flat plates abutted each other.

Summary of the invention The present invention, which makes use of a plurality of small easily replaceable blocks or inserts to a cylindrical surface, results in the rapid replacement of those areas having damaged projections. The inserts by being relatively small are inexpensive to cast and because of their low unit cost could be readily discarded rather than rebuilt at a large expense, whereas the large plates are too costly to discard and must be rebuilt. The individual small inserts may also be rapidly replaced on the production line resulting in less downtime than would exist where large plates must be removed and rebuilt.

The particular shape of the inserts and their arrangement on the cylindrical surface eliminate the existence of a rather lengthy straight-line abutment that will not have any fissure producing projections. Such an arrangement removes a rather noticeable pattern repeating design on the acoustical material.

Finally this invention makes more feasible the use of a rotary fissuring device as opposed to the fiat plate fissuring device. The greater practicality in the use of the rotary fissuring device results in an increased production speed, a relieving of the problems of stripping the acoustical material from the fissuring device, and provides for more flexibility in the size of the acoustical materials.

Brief description of the drawings FIG. 1 shows a cylindrical surface with a plurality of the inserts mounted thereon;

FIG. 2 shows an end view of a cylindrical surface with one insert mounted thereon;

'ice

FIG. 3 shows an enlarged view of an individual insert of preferred design; and

FIGS. 4-9 show related embodiments with different polygonal shapes.

Description of the preferred embodiment The cylindrical drum 2 forms the support for the individual fissuring inserts 4 which are removably attached to thedrum by a screw 6. The hexagonal shape of the individual inserts permits the adjacent rows of inserts to be staggered relative to each other so that no straight line abutting surface exists either laterally or longitudinally of the complete cylindrical surface. The inability to place fissuring projections at the abutting edges of the inserts extending across the length of the rotary support results in a rather noticeable line being produced on the acoustical material. By using hexagonal inserts with their staggered. placement, the former straight abutting surface is broken up into a series of short ofiset abutting surfaces which blend with the overall pattern to eliminate any noticeable repeat pattern on the finished product.

As seen in FIG. 3, each insert is hexagonal in shape and has a series of projections 8 for forming elongated fissures and a series of pins 10 for forming punch marks. Both the elongated fissures and the punch marks contribute to the sound absorbing quality of the acoustical product.

As seen in FIG. 2, each block has a curved rear surface so that it will mate with the rotary support. The sides of the hexagonal insert are also shaped so that adjacent blocks will be in a close abutting relationship.

The insert is normally made as a casting but could be formed by inserting fissure forming projections into a hexagonal base. The pattern arrangement of the individual projections 8 and 10 can readily be varied to provide other surface texturing operations.

FIGS. 4-9 show other related embodiments which provide the same effect as the hexagonally shaped insert. With each embodiment the sides form a polygonal shape which has straight or curved lines forming the sides of the closed figure. The structural characteristic of the polygonal shape is that the sides are related to each other and adjacent similar polygons so that the abutment surfaces thereof are staggered and do not form a straightline abutment line across the surface carrying the polygonal shapes.

From the foregoing it is to be understood that the invention is not limited to the illustrative embodiment shown in the drawings, and that all forms and modifications are contemplated as falling within the scope of the invention as expressed in the appended claims.

I claim:

1. An insert for forming fissures in acoustical materials comprising a block having a polygonal shaped sidewall arrangement with a base adapted to be mounted to a support surface and the opposite surface carrying a plurality of projection means for forming fissures, the polygonal shaped sidewall arrangement being the means for providing a staggered abutment line between a plurality of adjacent inserts.

2. The insert of claim 1 wherein the projection means are elongated.

3. The insert of claim 1 wherein the projection means are punch shaped.

4. The insert of claim 1 wherein the projection means are both elongated and punch shaped.

5. The insert of claim 1 wherein the polygonal shape is a hexagon.

6. A fissure-forming device comprising a cylindrical support means having a plurality of polygonal shaped inserts mounted thereon, the back surface of the insert conforming in shape to the support means, the opposite surface carrying a plurality of projection means for forming a fissured pattern on a surface adapted to receive the pattern, the side means of the inserts being arranged in a polygonal pattern so that adjacent rows of inserts when abutting together are staggered relative to each other so that the abutting edges of the inserts do not form a straight-line abutment line across the surface of the composite rotary structure, the polygonal shaped sidewall arrangement being the means for providing for a staggered abutment line on the pattern receiving surface whereby the abutment line blends in with the overall pattern.

References Cited UNITED STATES PATENTS WILLIAM S. LAWSON, Primary Examiner U.S. Cl. X.R. 

